Head in the clouds: two new microendemic tepui-summit species of Stefania (Anura: Hemiphractidae).

In addition to the type locality (the summit of Aprada-tepui, Bolívar State of Venezuela), the distribution of the egg-brooding frog Stefania satelles was long thought to include several isolated tabletop mountain (tepui) summits surrounding the large Chimantá Massif in Bolívar State (hence the Latin name "satelles"). However, multilocus molecular phylogenetic analyses have revealed that this taxon includes several undescribed morphologically cryptic species, and that S. satelles should be restricted to its type locality. Two tepui-summit species confused under that name in the literature remain to be named, and the present paper aims at describing these populations previously referred to as Stefania sp. 3 and S. sp. 5. Stefania sp. 3 is only known from the small summit of Angasima-tepui, while S. sp. 5 is only reported from the small summit of Upuigma-tepui, both mountains being located south of the Chimantá Massif. These new, phylogenetically distinct species are described based on external morphology and osteology and in comparison to close relatives in the S. ginesi clade, which consists exclusively of tepui summit species. Both new species have highly restricted geographic ranges (less than 3 km2) and should be listed as Critically Endangered according to IUCN criteria.

Diversification of the terrestrial frog genus Anomaloglossus (Anura, Aromobatidae) in the Guiana Shield proceeded from highlands to lowlands, with successive loss and reacquisition of endotrophy.

Two main landscapes emerge from the Guiana Shield: the highlands to the west called the Pantepui region and the Amazonian lowlands to the east, both harbouring numerous endemic species. With 32 currently recognized species, the genus Anomaloglossus stands out among Neotropical frogs as one that diversified only within the Guiana Shield both in the highlands and the lowlands. We present a time-calibrated phylogeny obtained by using combined mitogenomic and nuclear DNA, which suggests that the genus originates from Pantepui where extant lineages started diversifying around 21 Ma, and subsequently (ca. 17 Ma) dispersed during the Miocene Climatic Optimum to the lowlands of the eastern Guiana Shield where the ability to produce endotrophic tadpoles evolved. Further diversification within the lowlands in the A. stepheni group notably led to an evolutionary reversal toward exotrophy in one species group during the late Miocene, followed by reacquisition of endotrophy during the Pleistocene. These successive shifts of reproductive mode seem to have accompanied climatic oscillations. Long dry periods might have triggered evolution of exotrophy, whereas wetter climates favoured endotrophic forms, enabling colonization of terrestrial habitats distant from water. Acquisition, loss, and reacquisition of endotrophy makes Anomaloglossus unique among frogs and may largely explain the current species diversity. The micro evolutionary processes involved in these rapid shifts of reproductive mode remain to be revealed.

Thriving in a hostile world: Insights from the dietary strategy of two allopatric, closely related tepui summit endemic amphibians.

To date, there has been no published investigation on the trophic diversity in any tepui summit vertebrate. In this paper, we analyzed the dietary composition of a tepui summit endemic toad, Oreophrynella quelchii from Roraima-tepui, and compared it with that of O. nigra from Kukenán-tepui, to examine to what extent diet differs between these two sister species across isolated, although neighboring, tepui tops. The digestive tracts of a total of 197 toads were dissected: 111 from O. quelchii and 86 from O. nigra. The diet composition of O. quelchii was relatively diverse, with 13 major prey categories; mites (Acari, 36.5%) and beetles (Coleoptera, 21.0%) numerically dominated its diet. Despite occurring on two different tepui summits, O. quelchii and O. nigra exhibited a similar diet composition, although in O. nigra mites (Acari, 42.4%) and hymenopterans (especially ants, 16.9%) numerically dominated the diet. The present data suggest that tepui summit Oreophrynella species are flexible in their diet and are active foragers that also feed on aquatic arthropods, successful strategies in tepui competitive environments.

A New Species of Butterfly of the Genus Protopedaliodes from the Isolated Tramen Tepui in the Guyana Shield (Lepidoptera, Nymphalidae, Satyrinae).

A new species of Protopedaliodes Viloria & Pyrcz, a satyrine butterfly genus endemic to the highest part of the Guyana Shield, P. arekuna Pyrcz & Stachowicz n. sp., is described from the summit area, ca. 2400 m, of Tramen Tepui, an isolated mountain situated on the Venezuela-Guyana border. It is a remarkable finding as it is probably a narrow endemic, and only the fourth known member of the genus. Morphologically it most closely resembles P. kukenani Viloria & Pyrcz from the Roraima-Kukenán twin peaks. COI barcode analysis shows, however, high genetic distances between these two species, 9-10%. Protopedaliodes taxonomy is briefly revised, from the perspective of the monophyly of the genus based on preliminary molecular and morphological comparative data, including the female genitalia described for the first time for P. kukenani and P. ridouti Viloria & Pyrcz.

Phylogeny and biogeography of South American marsh pitcher plant genus Heliamphora (Sarraceniaceae) endemic to the Guiana Highlands.

Heliamphora is a genus of carnivorous pitcher plants endemic to the Guiana Highlands with fragmented distributions. We present a well resolved, time-calibrated, and comprehensive Heliamphora phylogeny estimated using Bayesian inference and maximum likelihood based on nuclear genes (26S, ITS, and PHYC) and secondary calibration. We used stochastic mapping to infer ancestral states of morphological characters and ecological traits. Our ancestral state estimations revealed that the pitcher drainage structures characteristic of the genus transformed from a hole to a slit in single clade, while other features (scape pubescence and hammock-like growth) have been gained and lost multiple times. Habitat was similarly labile in Heliamphora, with multiple transitions from the ancestral highland habitats into the lowlands. Using a Mantel test, we found closely related species tend to be geographically closely distributed. Placing our phylogeny in a historical context, major clades likely emerged through both vicariance and dispersal during the Miocene with more recent diversification driven by vertical displacement during the Pleistocene glacial-interglacial thermal oscillations. Despite the dynamic climatic history experienced by Heliamphora, the temperature changes brought by global warming pose a significant threat, particularly for those species at the highest elevations.

Beta diversity along an elevational gradient at the Pico da Neblina (Brazil): is spider (Arachnida-Araneae) community composition congruent with the Guayana region elevational zonation?

Beta diversity is usually high along elevational gradients. We studied a spider community at the Pico da Neblina (Brazil), an Amazonian mountain which is one of the southern components of the Guayana region. We sampled six elevations and investigated if beta diversity patterns correspond to the elevational division proposed for the region, between lowlands (up to 500 m), uplands (500 m to 1500 m), and highlands (>1500 m). Patterns of dominance increased with elevation along the gradient, especially at the two highest elevations, indicating that changes in composition may be accompanied by changes in species abundance distribution. Beta diversity recorded was very high, but the pattern observed was not in accordance with the elevationaldivision proposed for the region. While the highlands indeed harbored different fauna, the three lowest elevationshad similar species compositions, indicating that the lowlands spider community extends into the uplands zone. Other measures of compositional change, such as similarity indices and species indicator analysis, also support this pattern. Our results, in addition to a revision of the literature, confirm the high diversity and endemism rates of montane spider communities, and we stress the importance of protecting those environments, especially considering the climate crisis.

A rare new species of Leptohyphes Eaton (Ephemeroptera: Leptohyphidae) from the Lost World.

A new species of Leptohyphes Eaton (Ephemerotera: Leptohyphidae) is described, diagnosed and illustrated from nymphs collected in the Pantepui region in Southeastern Venezuela. Leptohyphes kukenan sp. nov. is similar to Leptohyphes populus Allen because they share a unique character for the genus: male compound eyes are divided. Other unique characters for the new species include a plesiomorphic gill structure, with imbricated ventral lamellae, and paired subapical denticles on tarsal claw. The new species show a unique combination of characters that distinguish it from L. populus and all other species of Leptohyphes: fore and hind margin of femora with spines on strong elevated sockets, part of body and legs covered by small pale spots, tarsal claws with 4-5 marginal denticles and a subapical pair of submarginal denticles, pronotum with large rounded lateral projection, hind wing pads absent in female, gill formula 8/7/7/4/1, operculate gill with imbricated ventral lobes, and gill V without ventral extension on dorsal lamella.

Enderleina preclara Jewett, 1960 (Plecoptera, Perlidae), from the Venezuelan Guayana-A description of a putative female, nymph and egg.

The putative female, nymph and egg of Enderleina preclara are described from specimens collected in the Kukenán-tepui foothills and Acopán-tepui foothills and plateau of Venezuela. Morphological and molecular approaches were employed to characterize these stages. Diagnostic keys for males and females of the described Enderleina species are also presented. The nymph is also morphologically compared with those of other Enderleina species. Comments on the ecology of this species and erroneous information regarding the putative type locality of E. preclara are provided.

Integrative overview of the herpetofauna from Serra da Mocidade, a granitic mountain range in northern Brazil.

The Brazilian mountain ranges from the Guiana Shield highlands are largely unexplored, with an understudied herpetofauna. Here the amphibian and reptile species diversity of the remote Serra da Mocidade mountain range, located in extreme northern Brazil, is reported upon, and biogeographical affinities and taxonomic highlights are discussed. A 22-days expedition to this mountain range was undertaken during which specimens were sampled at four distinct altitudinal levels (600, 960, 1,060 and 1,365 m above sea level) using six complementary methods. Specimens were identified through an integrated approach that considered morphological, bioacoustical, and molecular analyses. Fifty-one species (23 amphibians and 28 reptiles) were found, a comparable richness to other mountain ranges in the region. The recorded assemblage showed a mixed compositional influence from assemblages typical of other mountain ranges and lowland forest habitats in the region. Most of the taxa occupying the Serra da Mocidade mountain range are typical of the Guiana Shield or widely distributed in the Amazon. Extensions of known distribution ranges and candidate undescribed taxa are also recorded. This is the first herpetofaunal expedition that accessed the higher altitudinal levels of this mountain range, contributing to the basic knowledge of these groups in remote areas.

Determinación de áreas de endemismo en mosquitos (Diptera: Culicidae) en Venezuela, mediante criterios explícitos de optimización / Determination of areas of endemism in mosquitoes (Diptera: Culicidae) in Venezuela, through explicit optimization criteria

La familia culicidae ha sido estudiada ampliamente debido a su importancia en la salud pública y veterinaria. Varias especies de esta familia son vectores de múltiples patógenos que causan enfermedades que generan altas tasas de morbilidad y mortalidad, así como numerosas pérdidas económicas. El conocimiento de la distribución geográfica de este grupo y el análisis de su biogeografía histórica nos permitirán obtener más conocimientos acerca de su historia natural, de las razones geológicas y ecológicas de su distribución, así como de patrones epidemiológicos de las enfermedades de las cuales son vectores. La delimitación de áreas de endemismo (AE) es un paso inicial y fundamental para la realización de análisis de biogeografía histórica, para ello se elaboró una base de datos de 9.610 registros, 435 localidades, 20 géneros y 261 especies de Venezuela, a partir del cual se realizaron mapas de distribución, análisis explícitos de áreas de endemismos (AE) y parsimonioso de endemicidad (PAE) en los programas (software) NDM/VNDM. Los registros compilados de la familia culicidae se distribuyen principalmente al Norte del país, con distribuciones particulares hacia zonas montañosas o la región del Macizo Guayanés, entre otras. Se proponen tres áreas de endemismo para mosquitos: Macizo Guayanés-Pantepui, Región Norte-central y Cordillera Andina, las cuales son concordantes con las zonas ancestrales y recientes de la historia geológica del territorio.

The Family Culicidae has been studied extensively because of its importance in veterinary and public health. Several species of this family are vectors of pathogens causing multiple diseases which to generate high rates of morbidity and mortality and numerous economic losses. Studies of the geographical distribution of Culicidae and its historical biogeography analysis will allow us to obtain more knowledge about the natural history and explanations of geological and ecological reasons of the distribution and also the epidemiological patterns of diseases which are involved. The delimitation of areas of endemism (AE) is a crucial initial step for the analysis of historical biogeography and for this we developed a database of 9,610 records in 435 localities, 20 genera and 261 species from Venezuela, map distribution, and explicit analyzes of areas of endemism (AE) and parsimonious of endemicity (PAE) software NDM / VNDM. The records compiled of Culicidae are mainly distributed in the north of the country, with particular distributions to mountainous or Guayana Shield region, among others. The results suggest the proposal of three endemism areas for mosquitoes: Guayana Shield-Pantepui, North-Central Region and Andean mountains cordillera, which are concordant with recent and ancestral areas of the geological history of the country.